The present invention relates to a free run clutch apparatus. More specifically, the present invention relates to a free run clutch apparatus for damping movement of a device mechanically connected to the apparatus.
Free run clutch mechanisms have numerous applications for damping movement of a device mechanically connected to such clutch mechanism. Examples of such devices include ice maker doors for refrigerators, locker drawers, automobile ashtray lids and the like.
Such a free run clutch mechanism is extremely compact and yet provides reliable and robust dampening for a wide variety of applications.
However, because of the relatively small dimensions of the respective parts of the clutch mechanism, the assembly of the same has proved to be a labor intensive operation.
The free run clutch mechanism of the present invention greatly simplifies assembly of the mechanism and reduces the number of components required for such assembly.
Additionally, by the provision of a coating material on the spring of the clutch apparatus according to the present invention, a reduction in the generation of noise during operation of such clutch mechanism has been achieved.
Therefore, it is a feature of the present invention to provide a free run clutch mechanism that overcomes the problems associated with the prior art arrangements and which makes a considerable contribution to the art of manufacturing such a clutch mechanism.
Another feature of the present invention is the provision of a free run clutch mechanism which simplifies the assembly of such mechanism.
A further feature of the present invention is the provision of a free run clutch mechanism which has fewer parts compared to the prior art arrangements.
Another feature of the present invention is the provision of a free run clutch mechanism which is quiet in operation.
Other features and advantages of the free run clutch mechanism according to the present invention will be readily apparent to those skilled in the art by a consideration of the detailed description of a preferred embodiment of the invention contained herein.
The present invention relates to a free run clutch apparatus for damping movement of a device mechanically connected to the apparatus. The apparatus includes a housing which defines an enclosure and a rotor rotatably located within the enclosure, the rotor defining a cavity. A shaft has a first and a second end, the first end of the shaft being rotatably disposed within the cavity. A biasing device has a coating material applied thereto, the biasing device being disposed within the cavity between the first end of the shaft and the rotor such that when the shaft is rotated in a first direction, a free run of the biasing device within the cavity is permitted and when the shaft rotates in a second direction opposite to the first direction, the coated biasing device grabs the rotor so that dampening of the rotation of the shaft in the second direction can be achieved.
In a more specific embodiment of the present invention, the biasing device is a coil spring.
Also, the rotor defines a column and the coil spring expands and moves about the column when the shaft is rotated in the first direction. The coil spring contracts and tightens about the column so that the rotor can rotate when the shaft moves in the opposite second direction.
The coating material is a black oxide which is a conversion coating formed by a chemical reaction produced when the biasing device is immersed into an alkaline aqueous salt solution.
More specifically, the chemical reaction is produced when the biasing device is immersed into an oxide bath containing the salt solution in order to produce a magnetite coating on the biasing device.
Additionally, the apparatus includes a wax applied to the biasing device for assisting sliding of the biasing device within the cavity and the rotor is made from NYLON 66.
In one aspect of the present invention a damper assembly is provided for dampening movement of a device connected to the assembly. The assembly includes a coil spring coated with black oxide and a column which extends through the spring such that when the spring is rotated about the column in a first direction, the spring runs freely about the column and when the spring is rotated in a second direction opposite to the first direction about the column, the spring tightens into driving engagement with the column.
The apparatus further includes a housing which defines an enclosure and a rotor which is rotatably located within the enclosure, the rotor defining a cavity and the column. A shaft has a first and a second end, the first end of the shaft being rotatably disposed within the cavity. The spring is disposed within the cavity between the first end of the shaft and the rotor such that when the shaft is rotated in a first direction, a free run of the spring within the cavity is permitted and when the shaft rotates in a second direction opposite to the first direction, the coated spring grabs the rotor so that dampening of the rotation of the shaft in the second direction can be achieved.
The housing includes a first portion of cup-shaped configuration, the first portion having a base and a peripheral wall which extends from the base, the wall defining an internal cylindrical surface. A plurality of partitions extend from the base and are disposed within the enclosure, the plurality of partitions being disposed concentrically relative to the internal cylindrical surface. A plurality of anchoring ears extend radially away from the wall for anchoring the housing.
A second portion of cap-shaped configuration cooperates with the first portion for defining the enclosure so that the rotor is disposed between the first and second portions. The first portion further includes a central boss which extends from the base and is disposed concentrically relative to the plurality of partitions and the internal cylindrical surface for locating the rotor within the enclosure.
Moreover, the rotor includes a central member which defines a central aperture for the rotatable reception therein of the boss.
Additionally, the black oxide is a conversion coating formed by a chemical reaction produced when the biasing device is immersed into a hot alkaline aqueous salt solution. The chemical reaction is produced when the biasing device is immersed into an oxide bath containing the salt solution in order to produce a magnetite coating on the biasing device.
Also, a wax is applied to the spring for assisting sliding of the spring about the column.
In a further aspect of the present invention, a free run clutch apparatus for damping movement of a device mechanically connected to the apparatus includes a housing which defines an enclosure and a rotor rotatably located within the enclosure, the rotor defining a cavity. A shaft has a first and a second end, the first end of the shaft being rotatably disposed within the cavity. A biasing device has a black oxide coating material applied thereto, the biasing device being disposed within the cavity between the first end of the shaft and the rotor such that when the shaft is rotated in a first direction, a free run of the biasing device within the cavity is permitted. When the shaft rotates in a second direction opposite to the first direction, the coated biasing device grabs the rotor so that damping of the rotation of the shaft in the second direction can be achieved.
More particularly, the biasing device is a coil spring and the rotor defines a column. The coil spring expands and moves about the column when the shaft is rotated in the first direction. The coil spring contracts and is tightened about the column so that the rotor can rotate when the shaft moves in the opposite second direction.
The black oxide coating material is a conversion coating formed by a chemical reaction produced when the biasing device is immersed into a hot alkaline aqueous salt solution. The chemical reaction is produced when the biasing device is immersed into an oxide bath containing the salt solution in order to produce a magnetite coating on the biasing device.
Also, a wax is applied to the biasing device for added lubricity and rust protection and the rotor is made from NYLON 66.
The housing includes a first portion of cup-shaped configuration, the first portion having a base and a peripheral wall which extends from the base, the wall defining an internal cylindrical surface. A plurality of partitions extend from the base and are disposed within the enclosure, the plurality of partitions being disposed concentrically relative to the internal cylindrical surface. A plurality of anchoring ears extend radially away from the wall for anchoring the housing. A second portion of cap-shaped configuration cooperates with the first portion for defining the enclosure so that the rotor is disposed between the first and second portions.
The apparatus further includes a viscose dampening fluid disposed within the enclosure such that when the spring is tightened for driving the rotor, the dampening fluid dampens the movement of the rotor and the device mechanically connected to the apparatus. The fluid is a temperature stable viscous silicone fluid.
Additionally, the first end of the shaft defines a head. The bead includes an end face which rides on the column. A skirt portion extends from the end face, so that the skirt portion is slidably disposed within the cavity, the skirt portion defining a guide for guiding the biasing device. The second end of the shaft defines a keyed portion.
The coil spring has a first and a second extremity, the first extremity cooperating with the annular receptacle. The second extremity of the spring cooperates with the guide so that rotation of the shaft in the first direction slidably drives the first extremity of the spring against the cylindrical face of the cavity and when the shaft is rotated in the second direction, the first extremity of the spring cooperates with the cylindrical face thereby grabbing the cylindrical face so that the spring is tightened into driving engagement with the cylindrical face for rotating the rotor within the enclosure.
Furthermore, the second portion defines a bore for the rotatable reception therethrough of the shaft the second portion also defining an annular groove. An annular seal cooperates with the annular groove and the rotor when the first and second portions are assembled.
Also, a gear is secured to the second end of the shaft for cooperation with a mating gear on the device to be dampened.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features.